Plastic Driven Gear

[Richard2112]

Does anyone know where to get a plastic driven gear for the SM465 speedometer? I've searched and none of the ones I've seen look like the original.

[geezer#99]

Maybe here.


https://transmissioncenter.net/

[Richard2112]

Thank you for the reply geezer. That link has a ton of speedo gear parts. Since I don't know much about interchangeability, I may have to work specifically with speed gear size and tooth count.

I did a search on their site for sm465 and muncie. The first returned nothing and the second returned only a steel drive gear.
I know the 4wd has speedo gears at the transfer case but have no idea if they are the same as found in the 465 transmission.

I might end up with a box full of new speedo gears before I'm done.

My interest is primarily in finding a plastic driven gear. I'll make one if it comes to that.
Thanks for the link. I'll give them a call.

[geezer#99]

Instead of a box of speedo gears maybe you just need the right ratio adaptor.
Look on that link for some or ask them if you call.

[Richard2112]

You're right geezer, I do need an adapter to correct my speedometer reading. But I have modified an NV4500 to accept the speedo gear set from my sm465.
It seems to have worked ok but the steel gears are a bit noisey in the aluminum housing, especially when coasting.
I would really like to reduce the whirring sound of the gear set and I'm sure a plastic driven gear would do it. Just can't seem to find one.

[huntznsam]

Haven't needed them yet, but bookmarked this site just in case:
http://gearsmade.com/

[Richard2112]

Originally Posted by huntznsam

Haven't needed them yet, but bookmarked this site just in case:
http://gearsmade.com/

Thank you huntznsam. This may be just what I need.

[geezer#99]

Looks like Santa is gonna be good to you Richard!
That’s one awesome site!

[72blu]

I believe GM made speedo gears the same for all their transmissions of that time (Muncie/Saginaw/turbo350). I have never seen one like yours though which is odd. Although your original is metal you should get away with GM style plastic gear unless the drive gear inside the transmission was changed at some point. Summit sells pretty much all the speedo gears for GM transmission. You just have to find out what tooth count you need and you should be good to go. before you seal everything up, make sure you test the new gear to make sure it meshes properly inside otherwise you might be in for a headache.

[Richard2112]

Originally Posted by 72blu

I believe GM made speedo gears the same for all their transmissions of that time (Muncie/Saginaw/turbo350). I have never seen one like yours though which is odd. Although your original is metal you should get away with GM style plastic gear unless the drive gear inside the transmission was changed at some point. Summit sells pretty much all the speedo gears for GM transmission. You just have to find out what tooth count you need and you should be good to go. before you seal everything up, make sure you test the new gear to make sure it meshes properly inside otherwise you might be in for a headache.

Yeah I've been all over Summit and though there may be drive gears that will interchange, I'm reluctant to disassemble my extension housing to swap them. My primary interest is obtaining a plastic driven gear with the same dimensions as the one I installed. The driven gear must be steel because I cut my tone ring and put the driven gear on the shaft (between two sections of tone ring) with an interference fit of .002. The yoke nut holds them together and also holds my fifth gear. A plastic driven would be crushed and distorted. I am in the process of making a polymer driven gear now. If it doesnt work out, I'll have one made, I guess. It's already kind of a headache. Ha!

[Richard2112]

Originally Posted by geezer#99

Looks like Santa is gonna be good to you Richard!
That’s one awesome site!

Yeah I'll bet he is! I think I'll be in touch with that person. Looks like just what I was wanting for Christmas.